Gear-generating machine



May 6, 1924. 1,49%27 L. C. COLE GEAR GENERATING MACHINE Filed Dec. 12.1921 8 Sheets-Sheet 1 amvutoz May 6 1924.

L. C. COLE GEAR GENERATING MACHINE Filed Dec. 12 1921 8 Sheets-Sheet 2May 6, 1924;

L. C. COLE GEAR GENERATING MACHINE Filed Dec. 12. mm 8 Sheets-Sheet 4 Wl 2 W\\\\\\\\\ WV\\\\\ llllllllIllllllllllllllllllllllllllllfllllkllllll! fllllllllllIIlIllllll||IIlllll|IlllllIIllllllfllllalllllllllllMay 6 1924. 1,492,627

L. C. COLE GEAR GENERATING MACHINE Filed Dec. 12. 1921 8 Sheets-Sheet 5(inventor,

May 6 1924.

L. C. COLE GEAR GENERA TING MACHINE Filed Dec. 12. 1921 8 Sheets-Sheet 6May 6 1924.

L. c. COLE GEAR GENERATING MACHINE Filed Dec. 12 8 Sheets-Sheet May 6,1924. 1,492,627

| c. COLE GEAR GENERATING MACHINE Filed Dec. 12. 1921 8 Sheets-Sheet 8hventoz as l Patented 6, 1924 LYNDON C. COLE, OF HAMILTON, OHIO,ASSIGNOR TO NILES-BE NT-POWD CQMP 015 NEW YORK, N. Y., A CORPORATION' F3' 1: enne'rne'e Macmnn Application filed December 1%, 19%.

To all whom/it may concern:

Be it known that I, LYNnoN C. Gone, a citizen of the United States,residing at Hamilton, in the county of Butler and State 5 of Ohio, haveinvented certain new and useful Improvements in Gear-GeneratingMachines, of which the following is a specification.

This invent on rela es to a gear generating machine adapted to use arack form of cutter.

An object of the resent invention is to provide an improve geargenerating machine adapted for a wide range of sizes in which the toothcurves on the gear being formed may be generated by operation of acutter comprising a plurality of teeth of rack form.

One feature which enables me to accomplish the above object is that thegear to be generated is mounted on and rotated by a table supported nearone end of the base or bed of the machine, and the cutter, which asabove stated is of rack form, is mounted in a head which may movelaterall on a cross rail or saddle movable longitudinally along thebase. By positioning the cross rail or saddle at different distancesfrom the center of the table, gears of different diameters 83 within awide range may be generated.

Another object of the invention is to provide improved driving andpositioning means for the cutter and also for rotating the table withthe gear mounted thereon so 36 indexed between successive movements ofthe cutter.

Another object which is advantageous is that the support or housing forthe cutter is movable along the cross rail or saddle mounted on the basepredetermined precise distances and the table is adapted to be rotated acorresponding slight distance so that the gear and cutter may be movedrelatively to each other in a manner to simulate the intermeshin actionand movement of the gear and rac z. These means for rotating the tableand transversely moving the cutter support or head preferably com risesubstantially similar mechanisms an are used for rotating the tablethrough an angle subthat the table and gear may be expeditiously semino. sane.

tended by a portion only of the circular pitch of the gear beinggenerated, and for moving the rack cutter together with the cuttersupport laterally a predetermined distance equal to the same portion ofthe circular pitch to generate the tooth form. These means are referablmanually controlled independent y of eac by power means.

Another object of the invention is to utilize the above described tablerotating mechanism to rotatethe table and gear angularly through thedistance subtended by one tooth after each cutting stroke of the cutterduring which operation the cutter operating mechanism is stopped.

Another object which is advantageous is that the motors operating thecutter reciprocating and table indexing mechanisms are adapted to bealternately started and stopped and their circuits are so arranged thatboth motors cannot operate simultaneously. Preferably these mechanismsare controlled by means of the electrical circuits disclosed in theapplication of Harold L. Blood, Serial No. 422,592 filed November 8,1920.

Another object of the invention that is advantageous is that themechanisms are started and stopped by the movement of a cable extendingalong the base, one end of which is attached to an operative part of thetable indexing mechanism, and another part of the cable is engaged by amember operated by the cutter operating motor to pull the cable in adirection to release the table indexing mechanism and start its motor inoperation.

Another object of the invention is to provide means for preventing lostmotion between the table and its operating mechanism so that it may bepositioned accurately for each cutting stroke of the cutter ram.

With these and other objects in view, my invention consists in thefeatures of construction and operation set forth in the followingspecification and illustrated in the accompanying drawings.

In the accompanying drawin annexed hereto and forming a part of thisspecification, I have shown my invention embodied in a spur and helicalgear generating maother but are operated specification being relied uponfor that purose.

In the drawings:

Figure 1 is a plan view of the complete machine.

Fig. 2 is a side elevation of the machine with the cutter supportingmeans shown 1n its extreme forward position.

Fig. 3 is a front elevation of the machine.

Fig. 4 is a plan view partly in section of a portion of the tablerotating means.

Fig. 5 is an elevation partly in section of the table rotating means.

Fig. 6 is a vertical section taken on the line 66 of Fig. 4.

Fig. 7 is a vertical section taken longitudinally through the cuttersupport showlng the cutter and its reciprocating mechanism.

Fig. 8 is a front elevation partly in section of the cutterreciprocating mechanism.

Fig. 9 is a detail view partly in sectionof the indexing mechanismforthe table.

Fig. 9 is a fragmentary view on an enlarged scale of a part of themechanism shown in Fig. 9.

Fig. 10 is a vertical section of the indexing means taken on line 10-10of Fig. 9.

Fig. 10 is a fragmentary view of a part of the mechanism shown in Fig.10.

.Fig. 11 is a rear elevation partly in section of the complete machineshowing mechanism for controlling the cutter operating mechamsm.

Fig. 12 is a plan view of a part of the cable control mechanism.

Fig. 13 is an elevation of the same.

Fig. 14 is a diagrammatical view of the operative parts of the completemachine.

In the above mentioned drawings, I have shown but one modification ofthe invention which is now deemed preferable but it is to be understoodthat changes and modifications may be made within the scope of theclaims without departing from the spirit of the invention.

Briefly, my invention in its broadest aspect, comprises the followingprincipal parts; first, a bed having ways along its upper surface and avertical bearing for a ro tatable table near one end; second, a tablerotatable within the vertical bearing in the bed and adapted to mount agear; third, a cross rail or saddle movable toward and from said tablealong the longitudinal ways on the bed; fourth, a cutter head or housingmounted on said cross rail and adapted to move thereon transversely tothe movement of the saddle on the bed; fifth, means to rotate the tablestep by step one tooth at a timebetween movements ofthe cutter; sixth,indexing means? -mechanism for the table to rotate it through an anglecorresponding to a portion of the circular pitch of the gear; seventh,mechanism for laterally moving said cuttersupport a predetermined smalldistance; eighth, reciprocating means for the cutter; and nint mechanismto alternately operate the cutter and table rotating mechanism.

Referring more in detail to the figures of the drawing, at 10 is shownthe bed or base of a machine having a vertical opening 11 near one endin which is adapted to be rotated the work-carrying table 12. Preferablya thrust bearing 12 is provided adapted to carry the weight of the table12. This, as shown in Fig. 6, may be located'at. the lower end ofbearing 11. The depending portion of the table 12 is adapted torotatably engage the walls of the openingll. Extending along the uppersurface of the base 10 are ways 13, one being provided on either side.Along the ways 13 a saddle 14 is adapted to be moved. This saddle 14 hasways'15 on its upper surface disposed at right angles to the ways 13 onthe bed. To adjust the position of the saddle 14 toward or from thetable 12 along the ways 13 of the bed 10, a screw 16 is providedextending lengthwise of the bed 10 from the table 12 to the rear whichmay be rotated by a small motor 17 through suitable gearing 18. R0-tation of the motor 17 and therefore the screw 16 permits accurateadjustments of the position of the saddle 14 along the bed 10, theposition of the saddle 14 being indicated by a suitable scale 20 placedalong one side of the base. This scale 20 is preferably graduated intolengths of one inch, fractional parts of the inch through which thesaddle 4 is moved being indicated by'a graduated dial 21 (see Fig. 11)fastened to the extreme outer end of the screw 16.

Mounted on the saddle 14 so that it may be adjusted along the ways 15'is a cutter head or housing 25. v The position of this cutter head 25laterally of the bed 10 and along the ways 15 of the saddle 14 may beadjusted by rotation of a screw 26. Rotation of this screw 26 isaccomplished by the motor 27 The mechanism shown generally at 28 betweenthe motor 27 and screw 26 is adapted for moving the head 25 laterallypredetermined small distances and stopping it accurately in any desiredposition. This mechanism will be later described in detail.

The mechanism for operating the cutter and cutter ram will now bedescribed. On the forward surface of the head 25 is mounted the cutterram 30 to which may be clamped the cutter 31 which as shown. comprises aplurality of straight sided cutters corresponding to adjacent teeth of arack. This ram 30 and the cutter 31 are adapted to be moved up and downin a vertical plane by means of the screw 32, rotation of this screwbeing accomplished by the motor 33 mounted on the head 25. As usual withthis type of cutter, it may be withdrawn from operative position on thereturn stroke of the ram. Preferably, also, the cutter ram 30 iscounter-weighted. This may be conveniently accomplished by weights 30 oneither side of the ram 30 contained in openings in the head parallel tothe slideway 35 and connected with the slide by means of cables passingover wheels or pulleys 31 at the upper and lower ends of the oscillatingcutter ram support.

As shown in Figs. 7 and 8, the cutter ram 30 moves within a guideway 35formed centrally of a member 36, the ram 30 being retained by strips36*clamped on each side of the guideway. This member 36 as shown in Fig.7 is rotatably held adjacent the cutter head 25 by means of theprojection 37 formed integrally on the member 36 which is fitted withina circular depression 38'provided in the forward face of the cutter head25. Clamping bolts 39 permit fastening of the member 36 in any adjustedangular position. To angularly adjust the member 36 together with thecutter ram 30 and attached parts, a small motor 40 is used. This drivesa worm 41 through suitable reducing gearing 42. Worm 40 is in mesh witha segmental worm wheel 43 preferably formed integral with the'plate 36.Thus, by means of the motor 40, the cutter ram 30 may be positioned atany oblique angle with the ram movable in a vertical plane so thathelical gears of any desired helix angle may be formed.

To drive the cutter ram 30 along the guideway 35 during the cuttingoperation, the motor 33 previously mentioned is utilized. This, throughsuitable reducing gear 50, drives a horizontal shaft 51 locatedcentrally of the circular depression 38 in the housing 25 so thatangular adjustments of the plate 36 to the right or left will not affectits driving connection. At the forward end of shaft 51 is a bevel gear52 in mesh with a corresponding bevel gear 53 on a shaft 54 mounted inthe plate 36. Through a gear 55 on the upper end of shaft 54, gear 56on. the upper end of screw 32 isdriven. Rotation therefore of the motor33 rotates the screw 32 which, through a nut 57 on the comprise a gear62 in mesh with one of the cutter driving-gears 50 which drives a shaft63 and worm 64. Worm 64 drives a vertical shaft 65 which in turn drivesa horizontal shaft 66 extending along the saddle 14. Shaft 66 drivesshaft 67 through a pair of bevel gears 68, and shaft 67 drives the dial61 through bevel gears 69. Preferably, the dial 61 and shaft 67 aremounted on a bracket member 70, the position of which may be variedalong bed 10 in accordance with the various adjusted positions of thesaddle 14. Also, the motor 33 reverses its direction of rotation as soonas it reaches the lowest point for which it is set and, as soon as itreaches M its uppermost positions, its reversal of rotation is delayeduntil the indexing movement of the table 12 and gear has been completed.The means controlling these mechanisms will be described generally asthe specification proceeds.

Referring now to the mechanism for rotating the table 12 with a gearsuch as shown at A thereon, this comprises a motor which,throughmechanism 76, drives a set of change gears 78 and a driving shaft77. It is obvious that unless some means is provided for preventing backlash or lost motion between the parts of the driving mechanism betweenthe shaft 77, which forms the driving shaft for the table 12, and thetable itself that the position of the table 12 during the cuttingoperation may be slightly inaccurate. For that reason, I provide twodriving pinions, one of which is positively driven and the otherfrictionally driven at a slightly increased rate so that the table 12 isalways crowded to one side and all back lash or lost motion is taken upon the same side. These driving means comprise the driving shaft 77driven by motor 75 through the mechanism 76 presently to be fullydescribed. Rotation of the shaft 77 by the change gears 78 rotates theworm 79 formed integrally thereon which is in mesh with a worm gear 80at the in mesh with a gear 83 fastened to the table 12. It will thus beseen that rotation of the shaft 77 through the above described mechanismwill rotate the table 12 in either direction depending upon the rotationof the shaft 77. In the present embodiment of the invention, shaft 77 isrotated always in the same direction. I also provide a shaft 85 parallelto and driven by the shaft 77, as by gears 86 and 87, which has a worm88 there on in mesh with a worm wheel 89. As shown in Fig. 4, the shaft85 is driven from the shaft 77 at'an increased speed by reason of theratio between gears 86 and 87. The connection between the gear 87 andthe shaft 85 is through the friction driving clutch 88. It will be seentherefore that the shaft 85 is frictionally driven at a speed higherthan INT) 13m lower end of a vertical shaft 81. The shaft 81 has apinion 82 at its upper end which isshaft 77 and therefore rotates'theshaft 85 as far as permitted by the positively driven vertical shaft 81,the friction driving clutch -88? slipping to compensate for theincreased ratio between shafts 77 and 85. Worm wheel 89 IS on the lowerend of a shaft 90 which corresponds to shaft 81. At the upper end ofshaft 90 isa pinion 91 also in engagement with the table driving gear83. By means of the mechanism above described, the table 12 may be r0-tated through small angles and accuratel ositioned b means of rotationof the she t 77 without anger of its accuracy being effected by backlash or lost motion between elements of its driving connections.

Preferably, the change gears 78 (see Fig. 1) are so chosen that aninteger number of revolutions of a shaft 100, which comprises thedriving shaft for the change gears 78 and shaft 77, will rotate thetable 12 through an angle subtended by one circular pitch. For varyingnumbers of and sizes of teeth on the gear being cut, therefore, adifferent arrangement of the gears 78 is nezessary. These are, as shownin Figs. 1 and 2, arranged convenientl for the removal and substitutionof difi erent sizes of gears so that a proper gear ratio may be readilychosen.

The connections between the motor 7 5 and the shaft 100 by means ofwhich the shaft 100 is always stopped in a redetermined position willnow be describe These connections are contained within mechanismreferred to generally by 76. Referring to Figs. 9 and 10, detail viewsof mechanism 76 are shown. Armature shaft 101 of motor drives a shaft102 on which is fastened a worm 103. Preferably, the motor shaft 101drives worm shaft 102 through a friction driving clutch 104 so thatsudden stoppage of the mechanism 76 for driving the table 12 will notinjure the motor 75. Also a breaking link 105 is inserted between thefriction driving clutch 104 and the shaft 102 so that, should themechanism 76 be subjected to unduly large strains, thislink 105 willbreak before straining or distorting any of the table positioning meanswhich would have the effect of destroying the precision of the machine.In mesh with the worm 103 is a worm wheel 106 fast to the driving shaft100 of change gears 78. The function of the mechanism shown generally at76 is to providemeans for rotating the driving shaft 100 through exactlyinteger revolutions, and also to provide the means for accomplishing thefeeding or generative movements of the table. The starting of the motor75 to advance the table through an angle corresponding to the circularpitch of the teeth being cut is controlled by the cable 108 and motor 75is also stopped as soon as cable 108 is permitted to move in aeeaear theopposite direction. This is shown diagrammatically in Fig. 14, thecontroller for the motor 75 being shown at 75*. Movement of the arm 75to the left starts rotation of motor 75. -Operation of the cable 108 tostart motor 75 withdraws an index pawl 110 from engagement with anelongated arcuate slot 111 formed in the periphery of a disk 112-keyedto driving shaft 100. Upward movement of the pawl 110 therefore permitsrotation of disk 112 and the shaft 100. Immediately after startingrotation of the shaft 100 and disk 112, the pawl 110 is held in itsuppermost position by engagement of a projection 113 of the pawl 110with the periphery of the small rotatably mounted disk 114. As seen inFig. 9 t is small disk 114 is provided with a slot 115 permitting theprojection 113 to enter when this slot 115 and the elongated slot 111 indisk 112 are in alignment.

As above stated an integer number of revolutions of the shaft 100 andtherefore of the disk 112 are required to rotate or index the table 12through an angle corresponding to one circular pitch of the gear beingformed. This number may be one, or more, as for instance, five or six.It is obvious that unless some provision is made for rotating the smalldisk 114 more slowly than the disk 11.2, as soon as the disk 112 makesone revolution, the pawl 110 will drop into the slots 115 and 111 thuspreventing further rotation of shaft 100 and also stopping motor 75 bymovement of the controller 75 to the right. In order to permit aplurality of revolutions of the disk 112 and shaft 100, I provide aspecial driving means from shaft 100 for the small disk 114. Thiscomprises as shown in Figs. 9 and 10, a train of gears 116, one pair ofwhich may be changed to vary the ratio between driving gear 117 indriving connection with the shaft 100 and the gear on the shaft 118 withwhich the disk 114 is integrally formed. For a purpose presently to bedescribed, the driving connection be- I tween the gear 117 and the shaft100 comprises a pair of clutch jaws 119, these being so formed thatangular moveir-ent is permitted between the opposite jaw members (seeFig. 10). By changing the ratio between members of the gear train 116-any number of revolutions of the disk 112 and shaft 100 may take placebefore the slot 115 in disk 114 rotates sufficiently to permit the pawl110 to drop. This also must take place when the slot 111 in disk 110 isin alignment with slot 115.

Movement downward of the pawl 1.10 is accomplished by means of springs122 positioned adjacent the pawl 110. This movement of pawl 110 downwardserves to stop further rotation of shaft 100 by engagement of the pawl110 with one edge of the Means? arcuate slot 111. Simultaneously, bymovement of the cable 108, one end of which is attached, as shown, to alever 125 connected to the pawl 110, the motor is stopped by movement ofthe controller lever 7 5 to its off position (see diagram Fig. 14). Asthe motor 75 will probably not be stopped at precisely the same instantthat the pawl 110 drops, friction clutch 104 will sli and willyieldingly force the pawl 110 rmly against the wall of arcuate slot 111.

The above described part of mechanism 76 is used for rotating the table12 sufficiently to re-position the gear mounted thereon for the nextcutting stoke of the cutter ram 30. After the table 12 and gear havemade one complete revolution with the cutter 31 set to cut to the fulldepth of the teeth, the table 12 and cutter head 25 must be 50positioned relatively to each. other that the flanks of the cutter 31will out upon different parts of the involute profile of the gear teeth.This in effect comprises the feeding and generative movements by means.of which the cutter is fed relative to the gear and the tooth outlinesof the car are generated. This necessitates rotatm the table through afraction of a circu ar pitch and transversely moving the cutter head 25a corresponding linear distance. The means for thus rotating the table12 through this small angle is also contained in the mechanism showngenerally at 76. This will now be described.

The pawl 110 which in its upward position permits rotation of shaft 100and in its lower position stops further rotation of this shaft ismounted on a rotatable member 130, the periphery of which is providedwith teeth forming a wor wheel 131. Rotation of this member 130 -'saccomplished by turning shaft 132' having at one end a worm 133 engagingthe worm whee-l 131 and a hand wheel 134 atits outer end. Preferably, alost motion take-up is also provided comprising a shaft 135 driven fromshaft 132 through bevel gears 136, their ratio being such that shaft 135has a higher angular speed than shaft 132. On shaft 135 is a frictiondriving clutch 137 which drives a sleeve 138 surrounding shaft 135. Onsleeve 138 is a worm 139 meshing with worm wheel 131. serves to hold therotatable member 130 rigidly in adj usted position without lost motionand also permits manual adjustment of the position of the pawl 110angularly about the axis of shaft 100 by rotation of plate 130. p

In order to generate the tooth form accurately so that its outline willbe smooth from the root to the tip of the tooth, a number of cuts mustbe taken on each tooth with the cutter 31 in different positionsrelative to the tooth curves, so that the This mechanism cutter 31 cutsa smooth involute curve. With the table 12 and gear rotated through adefinite fraction of a circular pitch of the gear being formed, thecutter 31 must be laterally displaced a distance exactly correspondingthereto. The number of settings of the gear and cutter will varydependent upon the size and character of the teeth. I, therefore,provide means to adjust the angular position of the table 12 and lateralposition of cutter 31 in a pluralitv of exactly corresponding positions.To facilitate this and to aid in adjusting the gear and cutter 31predetermined corresponding small distances to properly form. the toothcurve outline, I mount a pawl 145- (see Figs. 9, 9 and 10) on thehousing of mechanism 76 and provide a handle 146 by means of which itmay be raised and lowered. An annular plate 147 is also provided rigidlyfastened to the mechanism 76 just below the pawl 145 into which awl 145may fit in its lower position. eyed to an extension'of the rotatablemember 130 is a plate 150 having notches 151 each corresponding in shapeto the forward end of pawl 145. These notches 151 are equidistantly-spaced about the periphery of the plate 150 and are also, forconvenience, numbered as shown. With the pawl 145 withdrawn from thenotches 148 and 151, the rotatable member 130 may be turned by means ofhandle 134 until any predetermined notch 151 in plate 150 is inalignment with the notch 148 in plate 147.

After the table 12 with its gear has been rotated through a completerevolution, the disk 130 may be angularly adjusted so that pawl 145 fitsinto another notch 151 adjacent to the notch 151 previously engaged bypawl 145. Then, when the disk 112 and shaft 100 have again been rotatedby motor 75, they will have been'rotated an integer number ofrevolutions plus a definite fraction depending on the new position ofthe disk 130.

The mechanism for transversely moving the cutter head 25 with the cutter31 as above stated comprises the screw 26, motor 2 7 and themechanism-28. Preferably, the mechanism 28 may be similar generally tothe mechanism 76 previously described for rotating the table 12 exceptthat the control cable is not connected as this mechanism is preferablymanually controlled. The pawl within mechanism 28 corresponding to pawl110 is controlled through a short cable 160 which may be normallycontrolled by hand lever 161 (see Fig. 1). The shaft 1.62 driven bymotor 27 through the mechanism 28 is in driving connection with screw 26through change gearing 163, the parts of which may readily be changed tovary the amount of rotation of screw26 for each rotation of shaft 162.In setting up the machine change gears 163 are so chosen that an integernumber of revolutions of shaft 162 moves the cutter head 25 a distanceequivalent to one circular pitch of the gear a being generated, thisinteger number bein the same as the number of turns require of shaft 100to rotate the table 12 through one circular pitch. A notched plate 150similar to plate 150 in mechanism 76 is also mounted on and forms a art.of mechanism 28 so that the cutter head 25 may be moved distancescorresponding to fractional parts of a circular pitch.

As above stated, the change gearing 163 is so chosen that the sameinteger number of revolutions are required of shaft 162 to move thecutter 21 transversely a distance equal to a circular pitch of the gearas are required of shaft 100 to rotate the table 12 through acorresponding arc. Then when the cutter 31 is to be moved transverselythrough a fractional part of a circular pitch, by setting the mechanism28 so that its pawl engages the notch corresponding with that on plate150, the cutter 31 may be moved through the same fractional part of acircular pitch. A small lever 1 16 corresponding to lever 146 permitsadjustment of the rotatable member 130 so that a pawl correspondin to145 may be positioned in notches of p ate 150. So long as the adjustmentis such that similarly numbered notchesin plates 150 and 150 areengaged; the. position of table 12 and cutter 31 are correct to properlygenerate an involute tooth curve.

Actual movement of the disk 112 and shaft 100 of the table rotatingmechanism 76 and the corresponding] parts of the cutter adjusting meanswit in mechanism 28 s not accomplished by rotation of member 130 and thecorresponding member 130 in mechanism 28. After these members 130 and130 have been adjusted to new angular positions, the next operation ofmotors 75 and 27 will rotate these parts and, on account of the newposition taken up 'by the arcuate slot 111 indiskf 112 and correspondingparts in mechanism 28, these disks will be stopped in a new position.Angular movement of members 130 and 130 by means of the shaft 132 andshaft in mechanism 27 corres nding thereto is permitted while the paw?in mechanism 76 and 28 are in their lowermost position by reason of thefact that the arcuate slots 111 extend around a part of thecircumference of the disks.

It is obvious that the rotative movement of table 12 and the transversemovement of cutter head 25 must correspond to the same fractional partof the circular pitch of the gear being generated. If, as above stated,shaft 162 makes the same integer number of turns to move the cutter h 26a distance between adjacent teeth on the aeeaear equal to the circularpitch as the shaft 100 makes to rotate the gear and table 12 through anangle subtended by one pitch, then equal fractional rotations of theshafts 100 and 162 move the table 12 and cutter head 25 equal fractionalparts of the circular pitch. We can, therefore, by rotating the member130 and its corresponding member 130 in mechanism 27 through the sameangle, the gear A and cutter 31 will given proper enerative movements.These movements 0 the cutter 31 and the gear being out are utilized toeflect their ceding movements. By ad'usting the mechanisms 76 and 28 sothat isk 130 and its corresponding member 130 assume a lurality ofcorresponding difierent positions separated by small fractions of thedistance gear being cut, the tooth curve formed will be smooththroughout its involute portion.

The cable 108 by means of which the motor 75 for rotating table 12 iscontrolled has previously been referred to. This is pulled in ad1rection to withdraw the pawl 110 and start motor 75 by the followingmechanism: Slidably mounted on the bracket is a rod 175 (see Fi 12 and13). This is reciprocated in eit er direction by means of the dogs 60 oncontroller disk 61 through oscillation of the arm 176, a part of whichis in the path of the dogs 60. At each limit of movement of the cutterram 30 in either direction, one of the dogs 60 strikes against the sideof arm 176 thus oscillating the al'ml 177 attached to the sliding rod175 by means of a connecting rod or link 177. On the rod 175 is a collar178 having a pawl 179 depending therefrom. This pawl is ivoted tobracket 17 8 by pin 180', the pawl 1 9 being so formed that it mayoscillate in one direction only namely to the left from the positionshown in Fig. 13.

Mounted on the bracket 70 is a frame 182 having a vertically movableplunger 183 held normall in its uppermost position by spring 184. Theupper end of plunger 183 which preferably is rovided with a roller 185is directly in t e path of pawl 179 and it is therefore depressed bymovement of the rod 175 to the left as seen in Fig. 13. Movement to theright of rod 175 does not depress the plunger 183 as the pawl 179oscillates about pin 180. Downward movement of plunger 183 oscillates abell crank 187, one arm of which abuts against the lower end of plunger183, the other arm of bell crank 187 being fastened to the cable 108 bya clamping screw 188. Move ment of the rod 175 to the left andoscillation of bell crank 187 therefore pulls the cable to the left thuswithdrawing pawl 110 and permitting motor to start. The return movementof cable is accomplished by the action of springs 122 and movementdownward of the pawl 110 as previously stated.

From the construction disclosed in Fig. 7, it is obvious that when thecutter ram 30 with itscutter 31 reaches its lowermost point, the motor33 must be reversed. This is accomplished by means of-a pilot switch 189shown diagrammatically in Figs. 13 and 14 which is oscillated by an arm190, the outer end of which is attached to' slidin rod 175. Rotation ofthe disk 61 throng its driving connections in the direction shown by thearrow in Fig. 14 moves the rod 175 to the left which through arm 190moves the pilot switch 189 to reverse motor 33 preparatory to thecutting stroke of the ram 30. Simultaneously, however, a switch notshown is opened thus preventing motor 33 from starting. This movement ofrod 175 to the left pulls the cable 108 through the mechanism describedand starts motor to index the table 12. As soon as the table indexingmovement is com lete, downward movement of pawl 110 pu ls the cable tothe right starting motor 33 on its cutting stroke and simultaneouslystopping motor 75.

Referring briefly to the operation of the above described machine, thegear to be cut is first mounted centrally of the table 12 and suitablyclamped thereto. This, as shown, takes a position such as shown by oneof the dotted circles A. The saddle 14 is then positioned on the base 10so that the cutter 31 will just cut into the periphery of the gear. Withthe saddle fixed in position the cutter. motor 33 is started and, bymeans of motor 75, the ear is rotated between each cutting stroke 0 thecutter 31 so that an adjacent tooth space of the gear will be cut oneach stroke of the cutter ram 30. This movement of the table 12 will, ofcourse, be accomplished automatically and the cutter 31- started andstopped by means of the control mechanism operated by do s 60 abovedescribed. After the table 12 with its gear A has made a complete turn,saddle 14 is then advanced toward the gear A and another turn of thegear takes place during which cutter 31 cuts further into depth. Afterthe cutter 31 has been advanced by means of saddle 14 until it cuts tofull depth of the teeth and the gear A has again been rotated a completerevolution, the relative positions of the cutter 31 and gear A must bealtered to feed the cutter 31 relative to the gear A so that it will cuton a difierent part of the tooth curve. This is accomplished by rotatingthe table 12 with its gear and transversely moving the cutter in amanner to simulate the relative movements of a gear and rack, thismovement of the cutter 31 being tangent to a pitch circle of the gearbeing cut. Rotating the gear is manually controlled by ad ustment ofmechanisms 76 and 28 so that when the cutter 31 is again operated, itcuts each tooth of the gear A in a slightly different portion of themvolute tooth curve. A number of different settings or adjustments ofthe table 12 and cutter 31 may be used, each adjustment taking placeafter the table and gear have made a complete turn.

Should one of the teeth of cutter 31 become worn or damaged, the cutter31 with its housing 25 may be readily moved laterally a distance equalto a full circular pitch of the gear being out, thus another tooth ofthe rack form cutter would be placed in position to do the major portionof the cutting.

What I claim is:

1. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near oneend,means to rotate said table, a transversely movable cutter support onsaid base, a cutter on said support, means to reciprocate said cutter,means to give said cutter and support generating lateral movements, andmeans to index said table and gear between reciprocations of saidcutter, said table indexing means being used also to rotate said tableand gear in accordance with generating lateral'movements of said cuttersup ort to accomplish feeding movements of t e gear relative to thecutter.

2. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end,means to rotate said table, a transversely movable cutter support onsaid base, a cutter movable on said support, means to reciprocate saidcutter, means to give said cutter predetermined small generating lateralmovements, and means to index said table and gear between reciprocationsof said cutter, said indexing means being used also to rotate said tableand gear in accordance with said generating lateral movements of saidcuttersupport to accomplish feeding movements of the gear relative tothe cutter.

3. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatablv mounted on said base near one end,means to rotate said table, a transversely movable cutter support onsaid base, a cutter movable on said support, means to move said supportand cutter predetermined distances tangentially of said table, means toreciprocate said cutter, and means to index said table and gearangularlyone tooth at a time between reciprocations of said cutter, saidindexing means being move said support laterall used also torotate saidtable and gear in accordance with generating lateral movements of saidcutter support to accomplish feeding movements of the gear relative tothe cutter.

4. A gear generating machine comprising incombination, a base, a tableadapted to support a gear rotatably mounted on said base near one end,means to rotate said table, a transversely movable cutter support onsaid base, a cutter'thereon, means to move said support and cutterpredetermined distances tangentially of sa1d table, m us to reci rocatesaid cutter at different ob ique ang es in a vertical plane, and meansto in: dex said table and gear between reciproca tions of the cutter,said indexing means being used also to rotatesaid table and gear inaccordance with generating lateral movements of said cutter support toaccomplish feeding movements of the gear relative to the cutter.

5. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end,means to rotate said table,

a transversely movable cutter support on said base, a cutter thereon,means to reciprocate said cutter variable distances, and means to indexsaid table and gear between reciprocations of the cutter, said indexingmeans being used also to rotate-said table and gear a portion of a toothspace in accordance with generating lateral movements. of said cuttersupport to accomplish feeding movementsof the gear relative to thecutter.

6. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end, asaddle movable along said base, a support on said saddle movabletransversely of said base, a cutter adapted to be reciprocated on saidsupport, means to index said table between each movement of the cutter,and means to rotate said table and predetermined co-relative amounts tosirm ate the rotating and sliding action of a gear and rack.

7. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end, asaddle movable along said base, a support 'on said saddle movabletransversely of said base, a. cutter adapted to be reciprocated on saidsupport, means to indexsaid table and gear angularly one tooth at atime, and means to rotate said table and move said housing laterallypredetermined co-relative amounts to simulate the rotating and slidingaction of a gear and rack.

8. A gear generating machine comprising in combination, abase. a tableadapted to support a gear rotatably mounted on said Y meaeav base nearone end, a saddle movable along said base, a support on said saddlemovable transversely of said base, a cutter adapted to be reciprocatedat different oblique angles in a vertical plane -on said support,

means to index said table and gear angusupport a gear rotatably mountedon said base near one end, a saddle movable alon said base, a support onsaid saddle movable I transversely of said base, to be reciprocated onsaid support, means to index said table between each movement of thecutter. and manually controlled means to a cutter adapted rotate saidtable and move said support laterall predetermined co-relative amountsto simu ate the rotating and sliding action'of a gear andrack after saidgear has completed a complete revolution.

10. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end, asaddle movable along said base, a support on said saddle movable.

transversely of said-base, a cutter adapted to be reciprocated on saidsupport, means to index said table between each movement of the cutter,and manually controlled means to rotate said table and move said supportin 'a'direction tangential to the pitch clrcle of said gear to simulatethe rotating and sliding action of a gear and rack after said gear hascompleted each revolution.

11. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end, acutter support on said base, a cutter slidably mounted thereon, andmeans to reciprocate said cutter, said means comprising a motor mountedon said support and driving connections including a screw," sald motorbeing adapted to be reversed at variable points in the stroke of saidcutter.

12. A gear generating machine compris' ing in combination, a base, atable adapted to support a gear rotatably mounted on said base near oneend, a cutter support on said base, a cutter slidably mounted in avertical plane thereon, and meansto reciprocate said cutter, said meanscomprising a motor mounted on said support and driving con nectionsincluding a screw, said motor being adapted to be reversed at variablepoints in the stroke of said cutter.

13. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end, acutter support on said base, a cutter slidably mounted thereon, ax; i

meansto reciprocate said cutter, said means comprising a motor mountedon said sup- ,port and driving connections including a screw, said motorbeing adapted to be reversed at variable points in the stroke of saidcutter and stopped in its uppermost position after each cutting stroke.

15. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end, acutter support on said base, a cutter slidably mounted thereon, andmeans to reciprocate said cutter in angularly adjustable verticalplanes, said means comprising a motor mounted on said support anddriving connections including a screw, said motor being adapted to bereversed at variable points in the stroke of said cutter and stopped inits uppermost p sition after each cutting stroke.

16. A gear generating machine comprising in combination, a base, a tableadapted to support a gear rotatably mounted on said base near one end, acutter support on said base, a cutter thereon, means to reciprocate saidcutter, said means comprising a motor mounted on said support andconnected to a cutter driving member by a shaft extending in alignmentwith the axle of said tool supporting member and including a screw, andmeans to reverse said motor at variable points in the stroke of saidcutter.

17 A gear. generating machine comprising in combinationf'a base, a tableadapted to support a gear rotatably mounted on said base near one end, acutter support on said base, a cutter thereon, means to reciprocate saidcutter, said means comprising a motor mounted on said support andconnected to a cutter driving member by a shaft extending in alignmentwith the axis of said tool supporting member and including a screw,means to reverse said motor at variable points in the stroke of the toolslide, and means to stop said motor when said cutter reaches itsuppermost position after each cutting stroke.

18. A gear generating machine comprising in combination, a base, a tablerotatably mounted thereon near one end and adapted to mount a gear,means to index said table, a cutter support on said base, means toreciprocate a cutter past the face of said sa1d means to index saidtable and reciprocate said -cutter comprising motors, and meanscontrolling said motors whereby they are alternately operated.

19 A gear generating machine comprismg in combination, a base, a tablerotatably mounted thereon near one end and adapted to mount a gear,means to index said table, a cutter support on said base, means toreciprocate a cutter past the face of said ear, sa1d means to index saidtable and reciprocate said cutter comprising motors, and meanscontrolling said motors whereby when one of said motors is stopped theother motor is started in operation.

20, A gear generating machine comprising in combination, a base, a tablerotatably mounted thereon near one end and adapted to mount a gear,means to index said table, a cutter support on said base, means toreciprocate a cutter past the face of said gear, said means to indexsaid table and reci rocate said cutter comprising indepen ent motors,and means controlling said motors whereby they are alternately operated.

21 A gear generating machine comprising in combination, a base, a tablerotatably mounted thereon near one end and adapted to mount a gear,means to index said table, a cutter support on said base, means toreciprocate a cutter past the face of said gear, sa1d means to indexsaid table and reciprocate said cutter comprising inde ndent motors, andmeans comprising a ca 1e controlling said motors whereby they arealternately operated.

22. A gear generating machine comprising in combination, a base, a tablerotatably mounted thereon near one end and adapted to mount a gear,means to index said table, a cutter support on said base, means toregear,

ciprocate a cutter past the face of said gear,

said means to index said table and reel rocate said cutter comprisinginde en ent motors, and means comprising a ca le, controlling saidmotors whereby when one of said motors is stopped the other motor isstarted in operation, and when the second motor is stopped the firstmotor is again started.

23. A gear generating machine comprising in combination, a base, a tablerotatably mounted thereon near one end and adapted to mount a gear,means to index said table, a cutter support on said base, means toreciprocate a cutter past the face of said gear, both of said means comrising motors, a

cable extending along sai base, means operated by said cutterreciprocating motor to pull said-cable in one direction to stop saidcutter reciprocating motor and start said table indexing motor, andmeans on said.

table indexing mechanism to pull said cable in the opposite direction tostop said table indexin motor when the indexing movement 0 said tablehas been completed and to start said cutter reciprocating motor.

24. A gear generating machine comprisingin combination, a base, a tablerotatably mounted thereon near one end and adapted to mount a gear,means to index said table, a cutter support on said base, meanstoreciprocate a cutter past the face of said gear, both ofsaid means comrising motors, a cable extending along sai base, means operated by saidcutter reciprocatmg motor to pull said cable in one direction to stopsaid cutter reciprocating motor and start said table indexing motor,means on said table indexing mechanism to pull said cable in theopposite direction to stop said table indexing motor when the indexingmovement of sald table has been completed and to start said cutterreciprocating motor, and means to reverse the cutter reciprocating motorduring its operation.

neeaeev 25. A gear generating machine comprising in combination, a base,a table rotatably mounted thereon near one end and adapted to mount agear, means to index said table, a cutter support on said base, means tore\ ciprocate a cutter past the face of said gear, both of said meanscomprising motors, a cable extending along said base, means operated bysaid cutter reciprocating motor to pull said cable in one direction tostop said cutter reciprocating motor and start said table indexingmotor, and means on said table indexing mechanism to pull said cable inthe opposite direction to stop said table indexin ment 0 said table hasbeen completed and. to start said cutter reciprocating motor wherebysaid motors are alternately and continuously operated.

In testimony whereof, I hereto aflix my signature.

LYNDON C. COLE.

motor when the indexing move

